Reflectarray Antenna Design (possibly using IE3D)

I have a question regarding Reflectarray Antenna Design (simple patch elements) using IE3D. I have previously used both HFSS and IE3D in the design of microwave circuits and simple patch antennas. However, in these experiences, the feed was physically attached to the antenna. Is it possible to simulate a structure where the feed is physically seperate from the antenna? I would like to excite the antenna from an external feed, offset from the array of reflector elements.

Also, i am concerned that HFSS will require too much memory for a large (possibly 40 elements or greater) array. This is my reason for considering using IE3D.

Any suggestions or better software for the job?

Thanks

no friend
it so difficult by HFSS
but using CST or Microstripes CST,i assure you can make your feeder offset from antenna

It is said that IE3D works only for planar structure, can't use the horn-feed.